1. Field of the Invention:
The present invention relates to temporary road marking devices and, more particularly, to a road marker having self righting characteristics for returning it to an upright position subsequent to the application of an externally applied force.
2. Description of the Prior Art:
Road markers, or traffic cones as they are commonly referred to in the art, are in wide usage for temporarily delineating obstructions. Traditionally, traffic cones have been in the form of upstanding hollow cones with planar bases slightly larger than the bottom ends of the cones to provide a degree of stability. The traffic cones are normally fabricated of a brightly colored synthetic resin and are light in weight for portability and to yield in reaction to an externally applied force rather than to damage the striking object, such as a motor vehicle.
For these reasons, traditional traffic cones are easily tipped over by a striking vehicle and even by the wind. Due to the relatively small size of the base and the semi-rigid nature of the materials used in fabricating the traditional traffic cones, once they are tipped over they remain that way and can cause a hazardous situation due to the significant loss of visibility of the tipped over traffic cone.
As a result of the tipping problem, some attempts have been made to devise an acceptable traffic cone which is more resistant to tipping over in response to an externally applied tipping force. One attempt has been that of fabricating the cones with larger bases and/or weighted bases. Such traffic cones have not achieved any degree of commercial success due to a number of factors, such as the increased fabrication costs associated with weighting of the bases, the significant loss of portability and increased handling difficulties.
U.S. Pat. No. 3,792,679 suggests that a cone be fabricated of a material having elasticity and flexibility characteristics which would tend to cause the cone to be self righting; that is, that it would tend to return to an upright position after being tipped over. This particular structure failed to achieve any appreciable degree of commercial acceptance for the same basic reasons mentioned above. In order for this particular cone structure to work properly, the base had to be large enough to maintain a portion in contact with the ground surface at all times during tipping and self righting movements. In the absence of a maintained ground surface contact, the traffic cone would remain in a tipped over state and would not right itself. The added weight of the base to make it large enough to accomplish this result reduced the portability and ease of handling sufficiently to contribute to its lack of success.
Accordingly, a need exists for a traffic cone effective to right itself after being tipped.